/**
 *  String format template
 *  - Inspired:
 *    https://github.com/Matt-Esch/string-template/index.js
 */

const RE_NARGS = /(%|)\{([0-9a-zA-Z_]+)\}/g;

export default function(Vue) {
    const { hasOwn } = Vue.util;

    /**
     * template
     *
     * @param {String} string
     * @param {Array} ...args
     * @return {String}
     */

    function template(string, ...args) {
        if (args.length === 1 && typeof args[0] === 'object') {
            args = args[0];
        }

        if (!args || !args.hasOwnProperty) {
            args = {};
        }

        return string.replace(RE_NARGS, (match, prefix, i, index) => {
            let result;

            if (string[index - 1] === '{' &&
                string[index + match.length] === '}') {
                return i;
            } else {
                result = hasOwn(args, i) ? args[i] : null;
                if (result === null || result === undefined) {
                    return '';
                }

                return result;
            }
        });
    }

    return template;
}
